We propose to employ an exciting new technology, "Imaging Cytometry", as a means to benefit and expand research activities at the University of Rochester Medical Center. The instrument we wish to purchase is a specially designed flow cytometer which has been adapted to provide multispectral images of individual cells. Known as the "ImageStream" cytometer, the device combines the power of traditional flow cytometric methods with the morphological analysis and intracellular imaging capabilities provided by microscopy. This powerful combination of technologies can be utilized for a broad spectrum of research applications. Specifically, the proposed studies will include (but not be limited to) analysis of human leukemia stem cells, development of red blood cells, interactions between T cells and antigen presenting cells, drug effects on lymphoma cells, manipulation of neuronal stem cells, studies of B cell anergy, nuclear trafficking of membrane phospholipids, lymphocyte responses to influenza virus, phosphoprotein analysis, and studies of platelet formation. These studies will be conducted by 23 independent investigators (9 major and 14 minor users), who collectively oversee 32 NIH grants supported by nine different NIH institutes. Taken together, the unique capabilities of the ImageStream system will therefore serve to strongly benefit a wide range of research activities. [unreadable] [unreadable] [unreadable]